Qur'an is the Holy Book of Islam and Sunnah is a term used to describe the practical example of the prophet of Islam, Muhammad.
The Quran provides the basic details about the five pillars of Islam which are:
Shahadah: reciting the Kalima
Salat: observing five daily prayers.
Zakat: paying charity on a prescribed rate.
Sawm: to fast in the month of Ramadhan.
Hajj: pilgrimage to Mecca.
The Sunnah explains the details of the above mentioned pillars in the acts of the prophet of Islam.